Scott Belcher, Ph.D.
North Carolina State University
NIEHS grantees found elevated levels of 11 per- and polyfluoroalkyl substances (PFAS) in the blood of Cape Fear River striped bass. The higher levels were associated with markers of altered immune and liver functions in the fish.
The team isolated serum from the blood of 58 wild striped bass caught in North Carolina’s Cape Fear River. The fish ranged in age from 2 to 7 years. Using a combination of liquid chromatography and high-resolution mass spectrometry, the researchers determined concentrations of 23 different PFAS chemicals present in serum. Results from the wild caught fish were compared with those from a reference population of 29 striped bass raised in an aquaculture facility that was fed by groundwater.
The average total PFAS concentrations in the wild caught bass were 40 times higher than the levels found in the reference population. Elevated levels of two of the PFAS chemicals, perfluorooctane sulfonate and Nafion byproduct 2, were found in 100% and 78% of the wild bass samples, respectively, compared with levels in Cape Fear River water. The serum concentrations of these compounds were associated with biomarkers of altered liver enzyme activity and immune function.
Unexpectedly, smaller fish had the highest levels of these chemicals. This finding suggests that PFAS may have different chemical properties than mercury and other chemicals that bioaccumulate. Such chemicals are often found at higher levels in larger fish. According to the authors, further studies are needed to define the specific factors influencing exposure, bioaccumulation, and the resulting adverse impacts of PFAS in fish.
Citation: Guillette TC, McCord J, Guillette M, Polera ME, Rachels K, Morgeson C, Kotlarz N, Knappe DRU, Reading BJ, Strynar M, Belcher SM. 2020. Elevated levels of per- and polyfluoroalkyl substances in Cape Fear River Striped Bass (Morone saxatilis) are associated with biomarkers of altered immune and liver function. Environ Int 136:105358.